A sphygmomanometer can be used to measure a patient's blood pressure in a non-invasive manner. In a typical example, a cuff is placed around the patient's arm and inflated. The cuff is deflated, and the blood starts to flow within the arm again. By monitoring the pressures at which the blood starts to flow (i.e., the maximum output pressure or systolic reading) and the pressure upon relaxation (i.e., the diastolic reading), an estimate of the patient's blood pressure readings can be obtained. Throughout the deflation of the cuff, arterial pressure changes cause pulsations or oscillations in the cuff pressure which have a correlation to the changing blood pressure in the underlying artery during a heart cycle.